The following information is provided to assist the reader in understanding technologies disclosed below and the environment in which such technologies may typically be used. The terms used herein are not intended to be limited to any particular narrow interpretation unless clearly stated otherwise in this document. References set forth herein may facilitate understanding of the technologies or the background thereof. The disclosure of all references cited herein are incorporated by reference.
Lung disease is one of the major healthcare problems present in the United States today. Respiratory failure is a syndrome in which the respiratory system fails in one or both of its gas exchange functions: oxygenation and carbon dioxide elimination. In practice, respiratory failure may be classified as either hypoxemic or hypercapnic. Hypoxemic respiratory failure, which is sometime referred to as type I respiratory failure, is characterized by an arterial oxygen tension (Pa O2) lower than 60 mm Hg with a normal or low arterial carbon dioxide (CO2) tension (Pa CO2). Hypoxemic respiratory failure is the most common form of respiratory failure. It may be associated with nearly all acute diseases of the lung. Hypercapnic respiratory failure, which is sometimes referred to as type II respiratory failure, is characterized by a PaCO2 higher than 50 mm Hg. Hypoxemia is also common in patients with hypercapnic respiratory failure who are breathing room air. Hypercapnic respiratory failure is, for example, commonly associated with severe airway disorders such as asthma, chronic obstructive pulmonary disease or COPD, and acute respiratory distress syndrome or ARDS.
Extracorporeal support systems are under development to effect carbon dioxide removal. However, clinical adaptation of developing extracorporeal carbon dioxide removal systems (ECCO2R) for management of hypercapnic respiratory failure has been hindered by the high blood flow rates necessary to provide adequate support. The high blood flow rates require a larger cannula inserted into the patient and increases the invasiveness of the procedure as a result.